-Dozens of conservatives and leaders of tea party groups from across Wisconsin are urging Gov. Scott Walker to "be the hero" and "boldly" reject Common Core education standards.

The letter delivered Tuesday to Walker comes after Assembly Republicans who studied the standards indicated they were not interested in abandoning them.

The voluntary standards cover English and math instruction and were adopted in Wisconsin three years ago.

The goal of the standards is to improve instruction and better prepare students for life after school. But critics, many of them conservative Republicans, say the standards are too weak and amount to the federal government creating a national curriculum.

Walker has said he would like to see Wisconsin adopt tougher standards. The letter urges him to completely reject the current standards.